Graded index optical fiber is effective in eliminating which of the following effects?

Graded index optical fiber is designed to mitigate modal dispersion, which is a key factor in limiting the bandwidth of multimode fibers. In graded index fiber, the refractive index of the core decreases gradually as one moves away from the center. This design allows light rays traveling down different paths or modes to traverse the fiber more uniformly, reducing the time it takes for these rays to reach the end of the fiber.

By minimizing the differences in travel time for the various modes, graded index fibers effectively reduce modal dispersion, leading to improved signal clarity and bandwidth over longer distances compared to step-index fibers. This is particularly important in high-speed data transmission, where clearer signals translate to better performance.

The other effects mentioned, such as chromatic dispersion, fiber attenuation, and jitter, are addressed through different design or material approaches and are not influenced by the graded index profile of the fiber. Chromatic dispersion occurs due to varying speeds of different wavelengths of light, fiber attenuation refers to the loss of signal strength over distance, and jitter pertains to timing variations in signal transmission.